Imperial Tropicals 1.5" Pleco Breeding Cave (D-Shaped Opening) These are great all around pleco breeding caves for smaller plecos such as bristlenose The opening is 1.5" tall and has a "D-Shape" profile, overall length is around 6-7" Made of natural stoneware clays and fired to 2200+ degrees making them inert Will not leach chemicals into the water and will not breakdown Made in the USA